Seedlings killed by fungus

(Question)

My first attempt at Pansy seedlings did not go well.  The package said to germinate at 20 to 25 degrees lightly covered. It didn’t say to keep them in the dark but it does everywhere else, so I wrapped the tray that had a high dome on it very loosely in a green garbage bag. I put them right next to my radiator.  At the bottom on the tray it was 21 to 23 degrees depending on distance from the rad.  After 2 days, I checked them and could see little white heads not off the soil yet.  I checked again the next day and there were sprouts but they had a fuzzy fungus on the stems.  Two days later they are dead.  This is very disappointing for my first attempt at seedlings.  I’m also doing it to save money and that 20 dollars could have bought quite a few pansies.  I’m wondering if this was such a good idea, but I now have a couple hundred dollars invested in seeds and equipment.  Do you have any suggestions?  I have enough pansy seeds left for another tray as I was going to start them later.

(Answer)

The green garbage bag is most likely the culprit as it probably caused high temperatures, fluctuating moisture levels and poor air circulation, leading to a condition known as “Damping Off” which can be caused by a number of fungal diseases.

White plastic film, aluminum foil or a piece of moist burlap placed on the seed bed would make a better cover to help keep seeds moist.

To help avoid the damping off problem, should you decide to try again, Thompson and Morgan seed producers offer the following  advice on their website:

https://www.thompson-morgan.com/where-did-i-go-wrong

Use fresh commercially produced soil medium instead of a half used bag left over from last season.

Always carefully wash and dry pots and trays before re-using them.

Don’t over water – let the soil medium dry out slightly between watering to keep fungal spread at bay.

Water with clean tap water instead of using rain water.

Keep seedlings well ventilated to ensure good air circulation.”

To help you decide whether growing from seed is the best option for you, Toronto Master Gardeners have put together a guide on growing from seeds that you might find useful.  For more information take a look at https://www.torontomastergardeners.ca/index.php/factsheet/growing-from-seed-a-toronto-master-gardener-guide/